In the manufacture of shingles, it has been known that when shingles are subjected to strong winds, the winds can engage the lower edges or tab portions of the shingles, and bend them upwardly.
On occasion, under strong winds, the tabs can bend upwardly in amounts sufficient that the inherent, internal resistance to substantial bending and perhaps cracking, can be overcome, in that the mat that is formed internally of the shingle, and the asphaltic material on the surfaces of the shingle, may not be sufficient to withstand certain wind conditions.
Various approaches have been made to resist shingle failure via cracking and the like, not all with substantial success.
For example, strips of adhesive material along lower ends of tabs of shingles have been applied, which, when subjected to hot weather conditions, softens an amount sufficient that such adhesive will adhere to the next-subjacent shingle on a roof, eventually harden and thereafter resist upward,deflection of shingle tabs under severe wind conditions. However, such adhesive sometimes dries out, offering reduced adhesion. In other cases, the wind conditions can exist during high temperature conditions when such adhesive located under tabs remains soft, and thus the adhesive does not function in its intended manner.
Other approaches have resorted to thickening the mat and/or asphaltic material, to offer internal resistance to bending, but nonetheless, failures due to wind-related bending of tabs of shingles continue to exist.
The present invention is directed toward providing a wind-resistant shingle, wherein a separate, exterior reinforcement layer is provided outside the rear surface of the shingle, with such layer comprising a material that is not coated or covered by any thick layer of asphalt or the like, such that the material that comprise the reinforcement assist in absorbing the torque that is applied to the shingle tabs by upwardly-lifting winds.
Accordingly, it is an object of this invention to provide a novel shingle having a wind-resistant layer on the lower surface of the shingle, that comprises a reinforcing material.
It is a further object of the invention to accomplish the above objects, wherein the reinforcement layer comprises a scrim material that includes lifting-torque absorbing strands.
It is another object of this invention to accomplish the above object, wherein the scrim extends into the tab portion of the shingle.
It is a further object of this invention to accomplish the objects above, wherein the shingle absorbs a high percentage of the lifting torque that is applied to the shingle, under conditions in which the tab edge of the shingle is lifted as much as or more than 45xc2x0.
It is a further object of this invention to provide a method of making shingles in accordance with the objects set forth above.
Other objects and advantages of the present invention will be readily understood upon a reading of the following brief descriptions of the drawing figures, detailed descriptions of the preferred embodiments and the appended claims.